The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 2013
Filed:
Feb. 01, 2011
Motohiro Ando, Kyoto, JP;
Motohiro Ando, Kyoto, JP;
Rohm Co., Ltd., Kyoto, JP;
Abstract
An abnormality detection circuit monitors the sink current Irnf of a H-bridge circuit and determines the presence of an abnormal state if the sink current is not detected for a predetermined time. The abnormality detection circuit includes a clock pulse generator, a counter and a NMOS transistor. The abnormality detection circuit includes a clock pulse generator arranged to generate a clock pulse of a predetermined frequency, and a counter arranged so that a count value is incremented every time the clock pulse is provided to the counter and arranged so that the count value is reset when the sink current is detected. The counter generates a first abnormality detection signal that changes from a normal logic level to an abnormal logic level when the count value reaches a predetermined value without being reset.